Role of Extracellular Vesicles in Pulmonary Arterial Hypertension: Modulation of Pulmonary Endothelial Function and Angiogenesis

Arterioscler Thromb Vasc Biol. 2020 Sep;40(9):2293-2309. doi: 10.1161/ATVBAHA.120.314152. Epub 2020 Aug 6.

Abstract

Objective: Extracellular vesicles (EVs) have the potential to act as intercellular communicators. The aims were to characterize circulating EVs in patients with pulmonary arterial hypertension (PAH) and to explore whether these EVs contribute to endothelial activation and angiogenesis. Approach and Results: Patients with PAH (n=70) and healthy controls (HC; n=20) were included in this cross-sectional study. EVs were characterized and human pulmonary endothelial cells (hPAECs) were incubated with purified EVs. Endothelial cell activity and proangiogenic markers were analyzed. Tube formation analysis was performed for hPAECs, and the involvement of PSGL-1 (P-selectin glycoprotein ligand 1) was evaluated. The numbers of CD62P+, CD144+, and CD235a EVs were higher in blood from PAH compared with HC. Thirteen proteins were differently expressed in PAH and HC EVs, where complement fragment C1q was the most significantly elevated protein (P=0.0009) in PAH EVs. Upon EVs-internalization in hPAECs, more PAH compared with HC EVs evaded lysosomes (P<0.01). As oppose to HC, PAH EVs stimulated hPAEC activation and induced transcription and translation of VEGF-A (vascular endothelial growth factor A; P<0.05) and FGF (fibroblast growth factor; P<0.005) which were released in the cell supernatant. These proangiogenic proteins were higher in patient with PAH plasma compered with HC. PAH EVs induced a complex network of angiotubes in vitro, which was abolished by inhibitory PSGL-1antibody. Anti-PSGL-1 also inhibited EV-induced endothelial cell activation and PAH EV dependent increase of VEGF-A.

Conclusions: Patients with PAH have higher levels of EVs harboring increased amounts of angiogenic proteins, which induce activation of hPAECs and in vitro angiogenesis. These effects were partly because of platelet-derived EVs evasion of lysosomes upon internalization within hPAEC and through possible involvement of P-selectin-PSGL-1 pathway.

Keywords: P-selectin; endothelial cells; extracellular vesicles; fibroblast growth factors; lysosomes; pulmonary arterial hypertension; vascular enothelial growth factor A.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Case-Control Studies
  • Cells, Cultured
  • Cross-Sectional Studies
  • Endothelial Cells / metabolism*
  • Endothelial Cells / ultrastructure
  • Endothelium, Vascular / metabolism*
  • Endothelium, Vascular / physiopathology
  • Endothelium, Vascular / ultrastructure
  • Extracellular Vesicles / metabolism*
  • Extracellular Vesicles / ultrastructure
  • Female
  • Fibroblast Growth Factor 2 / metabolism
  • Humans
  • Intercellular Adhesion Molecule-1 / metabolism
  • Male
  • Membrane Glycoproteins / metabolism
  • Middle Aged
  • Neovascularization, Physiologic*
  • P-Selectin / metabolism
  • Pulmonary Arterial Hypertension / metabolism*
  • Pulmonary Arterial Hypertension / pathology
  • Pulmonary Arterial Hypertension / physiopathology
  • Pulmonary Artery / metabolism*
  • Pulmonary Artery / physiopathology
  • Pulmonary Artery / ultrastructure
  • Signal Transduction
  • Vascular Endothelial Growth Factor A / metabolism
  • Vascular Endothelial Growth Factor Receptor-1 / metabolism

Substances

  • ICAM1 protein, human
  • Membrane Glycoproteins
  • P-Selectin
  • P-selectin ligand protein
  • SELP protein, human
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A
  • Fibroblast Growth Factor 2
  • Intercellular Adhesion Molecule-1
  • FLT1 protein, human
  • Vascular Endothelial Growth Factor Receptor-1